Lifting-jack



(No Model.)

J. CHURCH.

LIPTING JACK.

INVENTORZ ATTEST:

N, PETERS, Phoiuiilhngnphcn Washinglfll. I7. I;

' UNTTED STATES PATENT GFFIQE.

JAMES CHURCH, OF ST. LOUIS, MISSOURI.

LIFTlNG-JACK.

SPECIFICATION forming part of Letters Patent No. 258,556, dated May 30,1852.

Application filed April 30, 1880. (No model.)

To all whom it may concern.-

Be it known that I, JAMES Cannon, of St. Louis, in the State ofMissouri, have invented certain new and useful Improvements inLit'ting-Jacks; and I do hereby declare that the following is a full,clear, and exact description of the same, reference being had to theaccompanying drawings, and to the letters of reference marked thereon. I

This invention consists in certain construe tive features applicable toscrew lifting-jacks, as will hereinafter more fully appear.

In the drawings, Figure 1 isa side view, with parts removed, of myinvention as applied to screw lifting-jacks. Fig. 2 is a detailsectional plan at line as .r, Fig.1, ot' the device for rotating thescrew. Fig. 3 is a detail section at I I -l1ne a0 00,F1g. 1. I

The operating-screw is formed with right and left hand screw-threadedportions A B, which screw into the respective screw-th readed pieces 0D. These pieces are cast with their screw-threads in two parts, whichare afterward riveted or bolted together, as clearly indicated in Fig.3.

E is a gear-wheel, slightly beveled, arranged on the shank of theoperating-screw, the teeth 6 of which are engaged by one or more teeth,f,

of a tilting sleeve, F, which surrounds the construction forms a cheapand effective ratchet device for rotating the screws, avoiding as itdoes the use of separate pawls, springs, &c., usually required to effectthe purpose.

In use the teethfcan be moved down outof engagement with the gear-wheelE in the back motion of the sleeve F and moved up into engagement in theforward motion of the same when it is desired to force the parts 0 Dapart, and vice versa in drawing the parts 0 D together. The sleeve F isprovided with an eye or hollow extension, F, for the reception of anoperating-lever.

I elaim 1. The operating-screw provided with gearwheel E, in combinationwith a tilting sleeve or lever, F, having one or more teetl1,f, as andfor the purpose set forth.

2. The combination ofoperating-screws A B, parts 0 D, gear-wheel E,tilting sleeve F, and trethf, as and for the purpose set forth.

In testimony of said invention I have hereunto set my hand. 7 JAMESCHURCH.

In presence of- ROBERT BURNS, L. O. MoRsE.

